Dr. McMahan completed her Internal Medicine training at the University of Texas-Southwestern following her graduation from UTHealth Houston McGovern Medical School. She then completed her Rheumatology Fellowship at Johns Hopkins University and received a Master in Health Sciences (MHS) at the Johns Hopkins Bloomberg School of Public Health in 2011. She joined the faculty at the Johns Hopkins Scleroderma Center where she stayed for 11 years after completing her fellowship training in 2012. She was then recruited to join the University of Texas Health Science Center at Houston (UTHealth Houston) faculty in 2023 as Co-Director of the Scleroderma Program together with Drs. Mayes and Assassi. Dr. McMahan’s clinical and research expertise focuses on scleroderma (systemic sclerosis), particularly in the gastrointestinal complications of the disease.

Dr. McMahan’s research efforts are funded by the National Institutes of Health and other funding agencies. She conducts clinical and translational research on the gastrointestinal complications of scleroderma and is involved in clinical treatment trials to find better therapies for this disease. She has published over 60 articles and reviews in the medical literature describing her findings. She has contributed several book chapters for the benefit of physicians and patients.

Dr. McMahan co-leads the Gastrointestinal Working Group for the Scleroderma Clinical Trials Consortium and co-leads the GI ad hoc committee of the World Scleroderma Foundation. She has been actively involved in the American College of Rheumatology (ACR) for over a decade where she served on several committees and was on the Board of Directors. She now serves as the ACR Chair for the Committee on Finance.


Medical Degree
The University of Texas Health Science Center at Houston McGovern Medical School
The University of Texas-Southwestern - Internal Medicine
Johns Hopkins University - Rheumatology
Master’s in Clinical Research
Johns Hopkins Bloomberg School of Public Health